Autolytic changes in blood cells of human cadavers. II. Morphological studies.

The morphology of various types of cells in the peripheral blood of human cadavers was investigated. The material comprised 123 medicolegal autopsy cases with post-mortem (p.m.) times ranging fro 1.7 to 270.4 hours. The corpses were kept at +4 degrees C. The haematocrit values of the blood increased rapidly after death. The haematocrit-corrected red cell count, and the total white cell and platelet counts remained quite stable during the whole p.m. time range. Red cells were quite rapidly transformed from a discoid configuration to crumbled discs, echinocytes and spherocytes, but no debris or burst cell configurations were seen. Rapid deterioration of the staining properties and marked morphological changes in many leucocytes occurred quite rapidly after death. Lymphocytes seemed to be the most resistant and basophils the least resistant to the effects of autolysis. Morphologically altered platelets and aggregates of them were seen in each cadaver. The present morphological observations and the quantitative results suggest that various cellular elements of the blood seem to be quite resistant to autolytic effects, and many cells apparently retain their viability for longer periods of time in the blood of cadavers kept at reduced temperature.